Drakmor OS

A minimal operating system kernel written in Rust, designed for the x86-64 architecture.

📖 Description

Drakmor OS is a bare-metal operating system kernel project that demonstrates low-level system programming concepts using Rust. This project showcases:

• Bare-metal programming without the Rust standard library (#![no_std])
• Custom bootloader integration using the bootloader crate
• Direct hardware interaction through VGA buffer manipulation
• Memory safety in kernel-level code using Rust's ownership system
• Custom target specification for x86-64 bare-metal environment

The kernel currently implements basic VGA text mode output, serving as a foundation for building more advanced operating system features. This project is perfect for learning about:

• Operating system fundamentals
• Rust systems programming
• x86-64 architecture
• Bootloader protocols
• Memory management concepts

🛠️ Prerequisites

Before you can build and run Drakmor OS, ensure you have the following installed:

• Rust (latest nightly version)
• Cargo (comes with Rust)
• QEMU (for emulation)
• bootimage crate for creating bootable disk images

Installing Prerequisites

1. Install Rust:

   curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
   source ~/.cargo/env

2. Install QEMU:

   # On Ubuntu/Debian
   sudo apt install qemu-system-x86
   
   # On macOS
   brew install qemu
   
   # On Arch Linux
   sudo pacman -S qemu

3. Install bootimage:

   cargo install bootimage

4. Install required Rust components:

   rustup component add rust-src
   rustup component add llvm-tools-preview

📦 Installation & Setup

1. Clone the repository:

   git clone <repository-url>
   cd drakmor

2. Add the custom target:

   rustup target add x86_64-unknown-none

🚀 How to Build and Run

Building the Kernel

# Build the kernel
cargo build --target x86_64-drakmor.json

# Build in release mode for better performance
cargo build --target x86_64-drakmor.json --release

Creating a Bootable Image

# Create a bootable disk image
cargo bootimage --target x86_64-drakmor.json

Running in QEMU

# Run the OS in QEMU
qemu-system-x86_64 -drive format=raw,file=target/x86_64-drakmor/debug/bootimage-drakmor.bin

# Or with more verbose output
qemu-system-x86_64 -drive format=raw,file=target/x86_64-drakmor/debug/bootimage-drakmor.bin -serial stdio

Quick Run Command

For convenience, you can combine building and running:

cargo bootimage --target x86_64-drakmor.json && qemu-system-x86_64 -drive format=raw,file=target/x86_64-drakmor/debug/bootimage-drakmor.bin

🎯 Usage

Once you run the OS in QEMU, you should see:

• A black screen with "Hello World!" displayed in light cyan text
• The system will be in an infinite loop (as expected for a minimal kernel)

To exit QEMU:

• Press Ctrl+A then X (in the QEMU console)
• Or close the QEMU window

📁 Project Structure

drakmor/
├── src/
│   └── main.rs              # Main kernel entry point
├── .cargo/                  # Cargo configuration
├── target/                  # Build artifacts
├── Cargo.toml              # Project configuration
├── x86_64-drakmor.json     # Custom target specification
├── .gitignore              # Git ignore rules
└── README.md               # This file

🔧 Configuration Files

• Cargo.toml: Defines the project metadata, dependencies, and build profiles
• x86_64-drakmor.json: Custom target specification for bare-metal x86-64
• .cargo/config.toml: Cargo configuration for build settings (if present)

🤝 Contributing

Contributions are welcome! Here are some ways you can contribute:

1. Report bugs by creating an issue
2. Suggest features for the operating system
3. Submit pull requests with improvements or new features
4. Improve documentation and code comments

Development Guidelines

• Follow Rust coding conventions
• Add comments for complex low-level operations
• Test changes in QEMU before submitting
• Update documentation for new features